Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/prompt_toolkit/auto_suggest.py: 53%

1""" 

2`Fish-style <http://fishshell.com/>`_ like auto-suggestion. 

3 

4While a user types input in a certain buffer, suggestions are generated 

5(asynchronously.) Usually, they are displayed after the input. When the cursor 

6presses the right arrow and the cursor is at the end of the input, the 

7suggestion will be inserted. 

8 

9If you want the auto suggestions to be asynchronous (in a background thread), 

10because they take too much time, and could potentially block the event loop, 

11then wrap the :class:`.AutoSuggest` instance into a 

12:class:`.ThreadedAutoSuggest`. 

13""" 

14 

15from __future__ import annotations 

16 

17from abc import ABCMeta, abstractmethod 

18from typing import TYPE_CHECKING, Callable 

19 

20from prompt_toolkit.eventloop import run_in_executor_with_context 

21 

22from .document import Document 

23from .filters import Filter, to_filter 

24 

25if TYPE_CHECKING: 

26 from .buffer import Buffer 

27 

28__all__ = [ 

29 "Suggestion", 

30 "AutoSuggest", 

31 "ThreadedAutoSuggest", 

32 "DummyAutoSuggest", 

33 "AutoSuggestFromHistory", 

34 "ConditionalAutoSuggest", 

35 "DynamicAutoSuggest", 

36] 

37 

38 

39class Suggestion: 

40 """ 

41 Suggestion returned by an auto-suggest algorithm. 

42 

43 :param text: The suggestion text. 

44 """ 

45 

46 def __init__(self, text: str) -> None: 

47 self.text = text 

48 

49 def __repr__(self) -> str: 

50 return f"Suggestion({self.text})" 

51 

52 

53class AutoSuggest(metaclass=ABCMeta): 

54 """ 

55 Base class for auto suggestion implementations. 

56 """ 

57 

58 @abstractmethod 

59 def get_suggestion(self, buffer: Buffer, document: Document) -> Suggestion | None: 

60 """ 

61 Return `None` or a :class:`.Suggestion` instance. 

62 

63 We receive both :class:`~prompt_toolkit.buffer.Buffer` and 

64 :class:`~prompt_toolkit.document.Document`. The reason is that auto 

65 suggestions are retrieved asynchronously. (Like completions.) The 

66 buffer text could be changed in the meantime, but ``document`` contains 

67 the buffer document like it was at the start of the auto suggestion 

68 call. So, from here, don't access ``buffer.text``, but use 

69 ``document.text`` instead. 

70 

71 :param buffer: The :class:`~prompt_toolkit.buffer.Buffer` instance. 

72 :param document: The :class:`~prompt_toolkit.document.Document` instance. 

73 """ 

74 

75 async def get_suggestion_async( 

76 self, buff: Buffer, document: Document 

77 ) -> Suggestion | None: 

78 """ 

79 Return a :class:`.Future` which is set when the suggestions are ready. 

80 This function can be overloaded in order to provide an asynchronous 

81 implementation. 

82 """ 

83 return self.get_suggestion(buff, document) 

84 

85 

86class ThreadedAutoSuggest(AutoSuggest): 

87 """ 

88 Wrapper that runs auto suggestions in a thread. 

89 (Use this to prevent the user interface from becoming unresponsive if the 

90 generation of suggestions takes too much time.) 

91 """ 

92 

93 def __init__(self, auto_suggest: AutoSuggest) -> None: 

94 self.auto_suggest = auto_suggest 

95 

96 def get_suggestion(self, buff: Buffer, document: Document) -> Suggestion | None: 

97 return self.auto_suggest.get_suggestion(buff, document) 

98 

99 async def get_suggestion_async( 

100 self, buff: Buffer, document: Document 

101 ) -> Suggestion | None: 

102 """ 

103 Run the `get_suggestion` function in a thread. 

104 """ 

105 

106 def run_get_suggestion_thread() -> Suggestion | None: 

107 return self.get_suggestion(buff, document) 

108 

109 return await run_in_executor_with_context(run_get_suggestion_thread) 

110 

111 

112class DummyAutoSuggest(AutoSuggest): 

113 """ 

114 AutoSuggest class that doesn't return any suggestion. 

115 """ 

116 

117 def get_suggestion(self, buffer: Buffer, document: Document) -> Suggestion | None: 

118 return None # No suggestion 

119 

120 

121class AutoSuggestFromHistory(AutoSuggest): 

122 """ 

123 Give suggestions based on the lines in the history. 

124 """ 

125 

126 def get_suggestion(self, buffer: Buffer, document: Document) -> Suggestion | None: 

127 history = buffer.history 

128 

129 # Consider only the last line for the suggestion. 

130 text = document.text.rsplit("\n", 1)[-1] 

131 

132 # Only create a suggestion when this is not an empty line. 

133 if text.strip(): 

134 # Find first matching line in history. 

135 for string in reversed(list(history.get_strings())): 

136 for line in reversed(string.splitlines()): 

137 if line.startswith(text): 

138 return Suggestion(line[len(text) :]) 

139 

140 return None 

141 

142 

143class ConditionalAutoSuggest(AutoSuggest): 

144 """ 

145 Auto suggest that can be turned on and of according to a certain condition. 

146 """ 

147 

148 def __init__(self, auto_suggest: AutoSuggest, filter: bool | Filter) -> None: 

149 self.auto_suggest = auto_suggest 

150 self.filter = to_filter(filter) 

151 

152 def get_suggestion(self, buffer: Buffer, document: Document) -> Suggestion | None: 

153 if self.filter(): 

154 return self.auto_suggest.get_suggestion(buffer, document) 

155 

156 return None 

157 

158 

159class DynamicAutoSuggest(AutoSuggest): 

160 """ 

161 Validator class that can dynamically returns any Validator. 

162 

163 :param get_validator: Callable that returns a :class:`.Validator` instance. 

164 """ 

165 

166 def __init__(self, get_auto_suggest: Callable[[], AutoSuggest | None]) -> None: 

167 self.get_auto_suggest = get_auto_suggest 

168 

169 def get_suggestion(self, buff: Buffer, document: Document) -> Suggestion | None: 

170 auto_suggest = self.get_auto_suggest() or DummyAutoSuggest() 

171 return auto_suggest.get_suggestion(buff, document) 

172 

173 async def get_suggestion_async( 

174 self, buff: Buffer, document: Document 

175 ) -> Suggestion | None: 

176 auto_suggest = self.get_auto_suggest() or DummyAutoSuggest() 

177 return await auto_suggest.get_suggestion_async(buff, document)